Die mechanism



M.- SCHWARTZA I Re', 16,659

14 192 June 7 D1-E MEQHANISM Original Filed Dec. 10. 1923 Reissued June 1 4, 1927.

UNITED STATES v Re. 16,659 PATENT OFFICE.

MORRIS SCHWARTZ, OF CHICAGO, ILLINOIS, ASSIGNOR F ONE-HALF T0 WINNIFRD B. PARISH, OF CHICAGO, ILLINOIS.

Original No. 1,813,961,

My invention resides in an improved die mechanism adapted to the formation of hollow extensions of bodies of sheet material.

The mechanism of my invention enables l the formation of such extensions without cracks or fissures in the product. -The mechanism of my invention includesmale and female members and a spring yieldingly pressing one of the di-e members toward the other with a pressure sufficient to exert drawing engagement of the die members upon the materia interposed therebetween.

My invention is of particular service in the formation of tubular or cylindrical projections, and when thus employed the male member is in the form of a cylindrical punch having a conical workin end and the female member is rovided with a conical cavity conforming in shape to the conical end of the punch.

' Hitherto there was no tendency to dravvr the sheet material as the punch descended lwith the result that fissures were liable to format the bases of the extension.

By gripping the work between the two die membersthe sheet material is drawn as the die operates thereon to relieve the fissureforming tendency.

The invention will be more fully explained by reference to the accompanying drawing,

in which Fig. 1 is a view partially in section vand partially `in elevation of the preferred f orm of mechanism, the die members being in separated relation; Fig. 2 illustrates the punch and female member of the die in the early stage of an operation; Fig. 3 illustrates a later Stal; in the operation; Fig. 4 illustrates the al sta-ge' in the o ration; and Fig. 5 is a perspective view illiistrating the resulting product.

Like parts are indicated by similar characters o reference throughout the different figures 6 The male member 1 is shown in the form of a cylindrical punch having a tapering or conical workin end 2. The female member 3 is also pre erably, though not necesl sarily, cylindrical. This female'member is formed with a ta ering or conical cavit 5o that conforms in sliape to the conical punc end 2. There is a sup ort 5 for the' sheet material (illustrated at 6I; that is to be operated upon. This su port is formed with a cylindrical openingli which is of a. diameter con DIE MECHANISM.

mea January i1, 1927, seriez Ne. 679,796, inea December 1o, 192s. Application for reissue illed January 31, 1927. Serial No. 164,997.

forming to the external diameter of the tubular extension 8 (Fig. 5) that is to bel formed. The punch 1 conforms in size to the bore of the tubular extension 8. The annular clearance between the punch 1 and support 5 is substantially equal to the thickness of the sheet metal from which said tubularfextension is formed. Both die members are adapted to reciprocate in this opening in performing their function. The die member 3 carries vertical ins 9 which roject downwardly from the ase thereof, t ese pins sliding in vertical holes formed in the mounting v10 for the support 5. These pins bear upon a metal plate 11 which bears u on the top end of a spring cushion 12 ywhic is preferably a body of rubber..l This ,body of rubber is held in assembly with the plate 11 by means of the plate 13 engaging the bottom spring cushion, a bolt 14 screwed in the part 10, and a nut 15 upon the lower end of the'bolt, this nut clamping the cushion 12 between the plates 11 and 13.

As illustrated, the members of the'die are vertically arranged, the female member 3 and its supporting cushion 12 being lowermost. This cushiony exerts suicient preure to clamp the sheet metal 6, or other sheet ma'` terial, between the punch and female member with suicient force to cause the metal to be drawn downwardly as well as otherwise to be subject to the punching operation, wherer'by the sleeve 8 may be formed without the presence of fissures at its base. I prefer toL form a circular hole 16 in the sheet metal, there being left'sujficient metal between this hole and the borderof the opening 7 to form a sleeve 8 of the desired length when this much of the metal is added to by the metal drawn from the surrounding body of the sheet material.

While I have herein shown and particularly described the preferred embodiment of my invention I do not wish ,to be limitedto the precise details' of 'construction shown, as changes may readily be made without departing from the spirit of my invention; but

having thus described my invention, I claim punch upon the exterior of said support and having atapering working end; a female die member having a ta ering cavity receiving the tapering end oft e punchland normally 'received in an openin in said support, and

in which opening bot die members are reciprocable, and between Which support an'd the punchmcmber a clearance, 'substantially equal to the thickness of the sheet material being operated upon, intervenes to receive 10 the sheet material being worked upon; and

MORRIS SCHWARTZ.' u 

